Three-Dimensional Numerical Simulation Of Flow Field Of Debris Flow In Huyu Gully Basin,Xishan Region In Taiyuan

Debris flow is a typical solid-liquid two phase flow, ferocious, outbreak suddenly, it is frequent occurrence geological disaster in mountainous areas. Human struggle against the debris flows for a long time, with the urbanization process and economic construction activities push forward to the mountainous area, the mountainous area of debris flow hazards attaches great attention in various fields. main research contents of debris flow include:the generation mechanism of debris flow, the movement mechanism and movement characteristics; The rheological properties of the debris flow, accumulation characteristics and numerical simulation analysis; Debris flow hazard assessment, forecasting, control regionalization and design on treatment etc.Computational Fluid Dynamics (CFD) is a discipline established on the basis of classical fluid dynamics and numerical methods. on the basis of summing up the previous debris flow research, using computational fluid dynamics technology simulates debris flow of Huyu channel in Xishan of Taiyuan. The application software for the commercial CFD software ANSYS CFX, The research use the MAPGIS geographic information system and MIDAS-GTS establish3D model of Huyu channel, define the fluid of debris flow as Bingham viscous mud flow model, Through the simulation calculation obtain the size and distribution of debris flow velocity field and pressure field. Finally, carry on solid coupling simulation of debris flow Lan Dang engineering, come to the size and distribution of the impact of debris flow fluid worked on blocking dam body.Through research, following key conclusions have been made:(1)This study is based on three-dimensional contour through smoothing, thinning and assignment altitude for topographic contour in the MAPGIS, establishes three-dimensional valley model of the Huyu valley on the MIDAS-GTS platform, and proves that complex three-dimensional geological model can be easily and quickly built and the efficiency of the model of numerical simulation is greatly improved using before processing function。(2) The author discusses the classification and cause analysis of the debris flow, the rheological properties and motion characteristics of the fluid, and analyses the various rheological models of the debris flow on the basis of the different nature of the phenomenon of rheological characteristics, then does research on the theoretical foundation of computing the fluid dynamics, mesh generation during numerical simulation of the debris flow and the mash quality evaluation.(3) Taking the prevention and treatment on debris flow disaster of Huyugou in Taiyuan as an example and using ANSYS CFX, the author defines the debris flow fluid as the Bingham model, sets the initial and boundary conditions, adopts the reasonable control parameters and then simulates the flow field data such as the flow velocity and the pressure. Then, the simulated flow field data is imported into the finite element analysis software ANSYS to carry out calculations of the bank slope and fluid-solid coupling of the landslide dam. Finally, flow field characteristics of the debris flow and stress characteristics of the landslide dam are acquired to provide a reference for the design choice and planning of the debris flow prevention and control.